<script>

	
	let f = function(){}
	//f是一个方法类型的变量
	console.log(typeof f )  //输出变量的类型
	console.log(typeof "hello");
	console.log(typeof 123);
	console.log(typeof true);
	console.log(typeof undefined);
	
	//对象类型的变量
	let o = {};
	console.log(typeof o);
	
	//数组类型的变量   -- Object
	let ar = [];
	console.log(typeof ar);
	
	class Person{
		constructor(name,age){
			this.name=name;
			this.age=age;
		}
	}
	let p = new Person("jack",18);
	console.log(p instanceof Person);  //instanceof 判断对象是否是某个类的实例
	console.log(p);
	
	class Woman extends Person{
		
	}
	let w1 = new Woman("mary",28);
	console.log(w1);

	console.log("=============")
</script>